Hydroxy-functional fluoropolymers are known to be useful in coating compositions. For example, U.S. Pat. No. 4,345,057 details the synthesis of fluorinated ethylene-hydroxy-alkyl vinyl ether (FEVE) copolymers and their application in thermosetting coating compositions. Such coatings are useful in forming high gloss, durable topcoats for building panels, automotive body panels, and automotive body parts, among other things.
Notwithstanding their excellent properties, the use of hydroxyl-functional vinyl ethers as the source of the reactable hydroxyl group in these fluoropolymers provides a coating polymer that is relatively expensive. While the good durability of these FEVE coatings is known in the coatings industry, there is a need for more cost-effective fluoropolymers that can provide coatings having similar properties.
U.S. Pat. No. 6,153,697 discloses durable, chemically-resistant films made from terpolymers derived from fluoromonomers, olefins, and diesters of unsaturated anhydrides wherein at least one of the esterifying groups includes a hydroxyl group. While coatings containing such terpolymers may provide cost-efficient compositions that have many of the highly desirable properties of those derived from hydroxyl-functional fluoropolymers, such as those mentioned earlier, these compositions have the disadvantage of requiring the use of a diester of an unsaturated anhydride, which is a specialty monomer that is not necessarily readily available.
Thus, there is a need for fluoropolymers formed from readily available monomers, which are useful in providing thermosetting coating compositions that can result in cost-effective coatings having durability properties similar to those that include FEVE copolymers.